In the context of mine warfare, it is desirable to minimize the magnetic signature of ships. Magnetic signature means the strength of the magnetic field generated by the ship at a point located at a predetermined distance from the ship. Keeping the magnetic signature of a ship beneath a certain threshold prevents mines from triggering when the ship passes, since mines conventionally trigger on detection of a magnetic field above a predetermined threshold.
For this purpose, weakly magnetic towing winches, such as winches with hydraulic motors and mechanical or hydraulic brakes, are conventionally used. However, such winches have the drawback of requiring a hydraulic power unit on board the ship, as well as staff trained to carry out hydraulic maintenance tasks (routine maintenance and part replacement). Furthermore, these devices are large, costly and difficult to control.